On Thu, Apr 2, 2020 at 8:54 AM Andrey Konovalov <andreyknvl@xxxxxxxxxx> wrote: > > On Wed, Apr 1, 2020 at 8:09 PM 'Patricia Alfonso' via kasan-dev > <kasan-dev@xxxxxxxxxxxxxxxx> wrote: > > > > Integrate KASAN into KUnit testing framework. > > - Fail tests when KASAN reports an error that is not expected > > - Use KUNIT_EXPECT_KASAN_FAIL to expect a KASAN error in KASAN tests > > - Expected KASAN reports pass tests and are still printed when run > > without kunit_tool (kunit_tool still bypasses the report due to the > > test passing) > > - KUnit struct in current task used to keep track of the current test > > from KASAN code > > > > Make use of "[PATCH v3 kunit-next 1/2] kunit: generalize > > kunit_resource API beyond allocated resources" and "[PATCH v3 > > kunit-next 2/2] kunit: add support for named resources" from Alan > > Maguire [1] > > - A named resource is added to a test when a KASAN report is > > expected > > - This resource contains a struct for kasan_data containing > > booleans representing if a KASAN report is expected and if a > > KASAN report is found > > > > [1] (https://lore.kernel.org/linux-kselftest/1583251361-12748-1-git-send-email-alan.maguire@xxxxxxxxxx/T/#t) > > > > Signed-off-by: Patricia Alfonso <trishalfonso@xxxxxxxxxx> > > --- > > include/kunit/test.h | 5 +++++ > > include/linux/kasan.h | 6 ++++++ > > lib/kunit/test.c | 13 ++++++++----- > > lib/test_kasan.c | 37 +++++++++++++++++++++++++++++++++++++ > > mm/kasan/report.c | 33 +++++++++++++++++++++++++++++++++ > > 5 files changed, 89 insertions(+), 5 deletions(-) > > > > diff --git a/include/kunit/test.h b/include/kunit/test.h > > index ac59d18e6bab..1dc3d118f64b 100644 > > --- a/include/kunit/test.h > > +++ b/include/kunit/test.h > > @@ -225,6 +225,11 @@ struct kunit { > > struct list_head resources; /* Protected by lock. */ > > }; > > > > +static inline void kunit_set_failure(struct kunit *test) > > +{ > > + WRITE_ONCE(test->success, false); > > +} > > + > > void kunit_init_test(struct kunit *test, const char *name, char *log); > > > > int kunit_run_tests(struct kunit_suite *suite); > > diff --git a/include/linux/kasan.h b/include/linux/kasan.h > > index 5cde9e7c2664..148eaef3e003 100644 > > --- a/include/linux/kasan.h > > +++ b/include/linux/kasan.h > > @@ -14,6 +14,12 @@ struct task_struct; > > #include <asm/kasan.h> > > #include <asm/pgtable.h> > > > > +/* kasan_data struct is used in KUnit tests for KASAN expected failures */ > > +struct kunit_kasan_expectation { > > + bool report_expected; > > + bool report_found; > > +}; > > + > > extern unsigned char kasan_early_shadow_page[PAGE_SIZE]; > > extern pte_t kasan_early_shadow_pte[PTRS_PER_PTE]; > > extern pmd_t kasan_early_shadow_pmd[PTRS_PER_PMD]; > > diff --git a/lib/kunit/test.c b/lib/kunit/test.c > > index 2cb7c6220a00..030a3281591e 100644 > > --- a/lib/kunit/test.c > > +++ b/lib/kunit/test.c > > @@ -10,16 +10,12 @@ > > #include <linux/kernel.h> > > #include <linux/kref.h> > > #include <linux/sched/debug.h> > > +#include <linux/sched.h> > > > > #include "debugfs.h" > > #include "string-stream.h" > > #include "try-catch-impl.h" > > > > -static void kunit_set_failure(struct kunit *test) > > -{ > > - WRITE_ONCE(test->success, false); > > -} > > - > > static void kunit_print_tap_version(void) > > { > > static bool kunit_has_printed_tap_version; > > @@ -288,6 +284,10 @@ static void kunit_try_run_case(void *data) > > struct kunit_suite *suite = ctx->suite; > > struct kunit_case *test_case = ctx->test_case; > > > > +#if (IS_ENABLED(CONFIG_KASAN) && IS_ENABLED(CONFIG_KUNIT)) > > + current->kunit_test = test; > > +#endif /* IS_ENABLED(CONFIG_KASAN) && IS_ENABLED(CONFIG_KUNIT) */ > > + > > /* > > * kunit_run_case_internal may encounter a fatal error; if it does, > > * abort will be called, this thread will exit, and finally the parent > > @@ -603,6 +603,9 @@ void kunit_cleanup(struct kunit *test) > > spin_unlock(&test->lock); > > kunit_remove_resource(test, res); > > } > > +#if (IS_ENABLED(CONFIG_KASAN) && IS_ENABLED(CONFIG_KUNIT)) > > + current->kunit_test = NULL; > > +#endif /* IS_ENABLED(CONFIG_KASAN) && IS_ENABLED(CONFIG_KUNIT)*/ > > } > > EXPORT_SYMBOL_GPL(kunit_cleanup); > > > > diff --git a/lib/test_kasan.c b/lib/test_kasan.c > > index 3872d250ed2c..cf73c6bee81b 100644 > > --- a/lib/test_kasan.c > > +++ b/lib/test_kasan.c > > @@ -23,6 +23,43 @@ > > > > #include <asm/page.h> > > > > +#include <kunit/test.h> > > + > > +struct kunit_resource resource; > > +struct kunit_kasan_expectation fail_data; > > + > > +#define KUNIT_SET_KASAN_DATA(test) do { \ > > + fail_data.report_expected = true; \ > > + fail_data.report_found = false; \ > > + kunit_add_named_resource(test, \ > > + NULL, \ > > + NULL, \ > > + &resource, \ > > + "kasan_data", &fail_data); \ > > +} while (0) > > + > > +#define KUNIT_DO_EXPECT_KASAN_FAIL(test, condition) do { \ > > + struct kunit_resource *resource; \ > > + struct kunit_kasan_expectation *kasan_data; \ > > + condition; \ > > + resource = kunit_find_named_resource(test, "kasan_data"); \ > > + kasan_data = resource->data; \ > > + KUNIT_EXPECT_EQ(test, \ > > + kasan_data->report_expected, \ > > + kasan_data->report_found); \ > > + kunit_put_resource(resource); \ > > +} while (0) > > + > > +/** > > + * KUNIT_EXPECT_KASAN_FAIL() - Causes a test failure when the expression does > > + * not cause a KASAN error. > > + * > > + */ > > +#define KUNIT_EXPECT_KASAN_FAIL(test, condition) do { \ > > + KUNIT_SET_KASAN_DATA(test); \ > > + KUNIT_DO_EXPECT_KASAN_FAIL(test, condition); \ > > +} while (0) > > Any reason to split this macro into two parts? Do we call any of them > separately? > They are not called anywhere else... honestly, it was just a style choice to make it clear that there are 2 parts to the expectation. I don't think they have to be split if there's enough reason to smash them together. > > + > > /* > > * Note: test functions are marked noinline so that their names appear in > > * reports. > > diff --git a/mm/kasan/report.c b/mm/kasan/report.c > > index 5ef9f24f566b..87330ef3a99a 100644 > > --- a/mm/kasan/report.c > > +++ b/mm/kasan/report.c > > @@ -32,6 +32,8 @@ > > > > #include <asm/sections.h> > > > > +#include <kunit/test.h> > > + > > #include "kasan.h" > > #include "../slab.h" > > > > @@ -455,12 +457,38 @@ static bool report_enabled(void) > > return !test_and_set_bit(KASAN_BIT_REPORTED, &kasan_flags); > > } > > > > +#if IS_ENABLED(CONFIG_KUNIT) > > +void kasan_update_kunit_status(struct kunit *cur_test) > > +{ > > + struct kunit_resource *resource; > > + struct kunit_kasan_expectation *kasan_data; > > + > > + if (kunit_find_named_resource(cur_test, "kasan_data")) { > > + resource = kunit_find_named_resource(cur_test, "kasan_data"); > > + kasan_data = resource->data; > > + kasan_data->report_found = true; > > + > > + if (!kasan_data->report_expected) > > + kunit_set_failure(current->kunit_test); > > Hm, we only call KUNIT_SET_KASAN_DATA() for KASAN tests that we expect > to fail AFAICS. Then we end up calling kunit_set_failure twice, once > here and the other time when we do KUNIT_EXPECT_EQ() in > KUNIT_DO_EXPECT_KASAN_FAIL(). Or maybe there's something I > misunderstand. > You are right. I didn't realize, but yes. If the report_expected is false, KUNIT_DO_EXPECT_KASAN_FAIL() will set the test failure in KUNIT_EXPECT_EQ(). I think this is just leftover logic from before I thought to use KUNIT_EXPECT_EQ(). > > + else > > + return; > > Nit: "else return;" can be dropped. > > You can actually reorder the code a bit to make it easier to read: > > if (!kunit_find_named_resource(cur_test, "kasan_data")) { > kunit_set_failure(current->kunit_test); > return; > } > // here comes kasan tests checks > I agree. This looks much cleaner. The thing to note is that anyone can add a named resource to a test. I doubt anyone will name their resource "kasan_data" outside of this file, but it may be worth adding a comment advising against it. > > > > > > + } else > > + kunit_set_failure(current->kunit_test); > > +} > > +#endif /* IS_ENABLED(CONFIG_KUNIT) */ > > + > > void kasan_report_invalid_free(void *object, unsigned long ip) > > { > > unsigned long flags; > > u8 tag = get_tag(object); > > > > object = reset_tag(object); > > + > > +#if IS_ENABLED(CONFIG_KUNIT) > > + if (current->kunit_test) > > + kasan_update_kunit_status(current->kunit_test); > > +#endif /* IS_ENABLED(CONFIG_KUNIT) */ > > + > > start_report(&flags); > > pr_err("BUG: KASAN: double-free or invalid-free in %pS\n", (void *)ip); > > print_tags(tag, object); > > @@ -481,6 +509,11 @@ void __kasan_report(unsigned long addr, size_t size, bool is_write, unsigned lon > > if (likely(!report_enabled())) > > return; > > > > +#if IS_ENABLED(CONFIG_KUNIT) > > + if (current->kunit_test) > > + kasan_update_kunit_status(current->kunit_test); > > +#endif /* IS_ENABLED(CONFIG_KUNIT) */ > > + > > disable_trace_on_warning(); > > > > tagged_addr = (void *)addr; > > -- Thanks for the comments! Best, Patricia
